Questions
a. With the aid of appropriate sketches and thermodynamic analysis, describe the stages of a typical...

a. With the aid of appropriate sketches and thermodynamic analysis, describe the stages
of a typical Carnot cycle
b. 0.82 kg of air (ideal gas) executes a Carnot power cycle having a thermal efficiency of 34 percent. The heat transfer to the air during the isothermal expansion is 82 kJ. At the

In: Mechanical Engineering

4) A refrigerator in the kitchen at 30 ° C keeps the food section at -12...

4) A refrigerator in the kitchen at 30 ° C keeps the food section at -12 ° C. Refrigerant R-134a enters the evaporator located at the back of the freezer section of a home refrigerator with a degree of dryness of 100 kPa and 20 percent and exits at 100 kPa and -20 ° C. Since the compressor consumes 600 W and the COP of the refrigerator is 2.5, a) calculate the minimum flow (kW) required to keep the mass flow of the refrigerant, b) the heat released into the kitchen air (kW), c) the food section at -12 ° C. (20 point)

In: Mechanical Engineering

3) Air enters a compressor at 2 m / s, 20 ° C and 100 kPa...

3) Air enters a compressor at 2 m / s, 20 ° C and 100 kPa pressure, exits at 50 m / s, 900 kPa pressure and 200 ° C. Make sure that the power consumed by the compressor is 500 kW. The outlet cross-section diameter of the compressor is 10 cm. (Neglect the change in potential energy.) (15 points)

CALCULATE THE AMOUNT OF HEAT?

In: Mechanical Engineering

Define the following terms, (i) specific work transfer (ii) specific air consumption (iii) work ratio (iv)...

Define the following terms,
(i) specific work transfer
(ii) specific air consumption
(iii) work ratio
(iv) swept volume
b. DerivetheformulaforthemeaneffectivepressureoftheOttocycle
c. An engine of 200 mm bore and 315 mm stroke works on Otto Cycle. The clearance is
3O
0.00251 m . The initial pressure and temperature are 1 bar and 65 C. If the maximum
pressure is limited to 35 bar, calculate the following,
(i) The air standard efficiency of the cycle
(ii) The mean effective pressure for the cycle

In: Mechanical Engineering

A power station uses Diesel as fuel (C12H26), from the analysis of combustion gases, it's obtain...

A power station uses Diesel as fuel (C12H26), from the analysis of combustion gases, it's obtain that 30% of carbon is converted to CO and the rest to CO2.

Furthermore, the gases in the exhaust have a temperature of 450 K. with this information:

a) mass air-fuel ratio: In Kgair/Kgfuel

b) Theoric air percentage: %

c) Moles of water steam produced in the reaction: in kmol

d)"wasted" heat in the gases on the steam exhaust, if you consider that the ideal exit temprature of the combustion gases should be of 380K: in kJ/kg

In: Mechanical Engineering

i need summary between (4-10) pages about ((Control circuit refrigeration system in airplanes)) with name of...

i need summary between (4-10) pages about ((Control circuit refrigeration system in airplanes)) with name of the references in end page

In: Mechanical Engineering

Two equal gear wheel of 360 mm p.c.d and 6 module are in mesh if the...

Two equal gear wheel of 360 mm p.c.d and 6 module are in mesh if the pressure angle 20 determine the maximum addendum necessary if there are always to be at least two pairs of teeth in contact . if the gear wheels rorates at 110 r.p.m and 6 kw is being transmetted find the normal force between the teeth assuming that the total force is dividing equally between the two pairs of teeth Neglect the frection. (Ans 6.8mm , 1.54KN .)

In: Mechanical Engineering

Briefly describe (with the use of diagrams) the Brayton’s cycle and derive the formula for the...


Briefly describe (with the use of diagrams) the Brayton’s cycle and derive the formula for
the coefficient of performance for the Brayton’s cycl

In: Mechanical Engineering

A house that is losing heat to the 100C outdoors at an average rate of 50,000...

A house that is losing heat to the 100C outdoors at an average rate of 50,000 kJ/h is maintained at 220C at all
times during a winter night for 10 h. The house is to be heated by 50 glass containers each containing 20 L
(1L=10-3 m3
) of water that is heated to 80oC during the day by a solar heater. A thermostat-controlled 15-kW
back-up electric resistance heater turns on whenever necessary to keep the house at 220C. Analyse and
determine the following:
i. If the average solar intensity is 650 W/m2

and the solar heater has an efficiency of 80%, calculate the

area of solar heater to heat 20L of water from 220C to 800C in 8 hours.
ii. How long did the electric heating system run at night?
iii. Keeping 2nd law of thermodynamics in mind, what is the maximum efficiency of the back-up heater?
iv. If the heat provided by the back-up heater is provided using Carnot heat pump, determine the
reduction in electricity consumption.

In: Mechanical Engineering

Derive the general energy equation for the following systems using appropriate diagrams, (i) Internal combustion engine...

Derive the general energy equation for the following systems using appropriate diagrams,
(i) Internal combustion engine
(ii) Steam turbine
(iii) Boiler
(iv) Compressor

In: Mechanical Engineering

A machine is out of order for minor work. Define controls exercised in maintenance. Department required...

A machine is out of order for minor work. Define controls
exercised in maintenance. Department required for its maintenance.

In: Mechanical Engineering

ppt presentation on "Lifting Hazards"

ppt presentation on "Lifting Hazards"

In: Mechanical Engineering

a Describe briefly the main cost headings associated with achieving high quality and reliability, and the...

  1. a Describe briefly the main cost headings associated with achieving high quality and reliability, and the main consequential costs of failure, in development, production and use.

b Explain and discuss Deming’s philosophy of overall quality and reliability cost minimization.

In: Mechanical Engineering

Obtain the initial and residual shock spectra of a half sine pulse. What is the total...

Obtain the initial and residual shock spectra of a half sine pulse. What is the total shock spectrum?

In: Mechanical Engineering

need a presentation on "Lifting Hazards"

need a presentation on "Lifting Hazards"

In: Mechanical Engineering